The present invention relates to a new and improved construction of an overhead cable transport installation, especially an aerial cableway.
Generally speaking, the overhead cable transport installation, especially the aerial cableway of the present development is of the type comprising a conveying cable which revolvingly moves between two stations and vehicles or the like are decoupled or released from the travelling cable at the stations. Each station is provided with a transfer rail forming a respective inbound region and an outbound region. Friction wheels coupled with drive elements are arranged at the inbound region and the outbound region along the transfer rails. These friction wheels coact with friction plates of the vehicles which are supported upon the transfer rails. At least the portion of the friction wheels at the inbound region and the outbound region, when considered in relation to immediately neighboring friction wheels, possess different circumferential velocities in order to stepwise or incremently decelerate or brake inbound vehicles and to stepwise or incrementally accelerate outbound vehicles. The friction plates possess a length which is greater than the spacing between neighboring friction wheels having different circumferential velocities.
A chair lift or gondola lift of the aforementioned type has been disclosed in U.S. Pat. No. 4,563,955, granted Jan. 14, 1986.
The requirement that the length of the friction plate should be longer than the spacing or distance between two friction wheels, for instance constructed as pneumatic wheels or tires, is predicated upon the requirement that a vehicle, both during its acceleration and also during its deceleration, should always be controlled by at least one friction wheel, and thus, there must prevail a reliable engagement between its friction plate and this one friction wheel.
Because of the fact that in the case of an aerial cableway of such type two neighboring friction wheels must positively possess, along the acceleration path or deceleration or braking path, circumferential velocities which deviate from one another, there however results from the repetitive simultaneous engagement of two friction wheels with a friction plate a pronounced or marked wear and the resultant unintentionally performed frictional work is also at the expense of a corresponding expenditure in energy.
An overhead cable transport installation or aerial cableway which eliminates one of these drawbacks is known from the French Pat. No. 2,340,848. However, in this prior art construction of aerial cableway all of the friction wheels of one set always possess the same velocity. This velocity is increased for accelerating the vehicles and, as the case may be, decreased for decelerating or braking the vehicles, under the action of a variable drive or drive means which is controlled by a suitable control unit. This overhead cable transport installation or aerial cableway is, however, quite complicated in its design and prone to malfunction or disturbance since there are also required feelers or sensors which must be activated by the vehicles or the like.